- Previous studies detected both lethal and cumulative chromosomal aberrations in bone marrow and peripheral blood of patients with worn hip and knee replacements. This study shows that wear debris from a worn titanium metal on high-density polyethylene hip replacement also produces chromosomal instability and reproductive failure in cell culture. The progeny of these treated cells also displayed chromosomal instability, mainly consisting of chromatid breaks and minutes, and reproductive failure as determined by clonogenic survival many generations postexposure. These delayed effects are similar to those caused by the heavy metals cadmium and nickel and to those seen for low-dose radiation. These findings may have important implications with regard to the long-term risks of joint replacement surgery. This highlights the need for long-term epidemiological studies of patients with surgical implants.